Gold-Catalyzed Cyclization of Ynamides and Propargylic Carboxylates

Over the past few years new synthetic methodologies for the preparation of ynamides have led to a huge increase in their use as highly variable building blocks in organic synthesis. Owing to the presence of an electron-withdrawing group ynamides show a perfect balance between stability and reactivity. Furthermore, due to their strongly polarized triple bond, ynamides show a large variety of reactions possibilities. Among these there are, for example addition at the α- or β-position, cycloaddition, ring-closing metathesis, cyclosisomerization